| 摘要 |
1,203,336. Electric permutation locks. C. J. ALFONSI. 17 June, 1968 [20 June, l967], No. 28749/68. Heading E2A. An anti-theft device for a motor vehicle comprises a transistorised switching circuit designed so as to be responsive both to the setting of a rotary selector contact K4 and to the operation of one or more other switching devices, e.g. ignition switch K1, a switch K2 operated if casing 21 of the rotary selector contact is tampered with, or a switch K3 operated if the vehicle bonnet is opened, completion of a circuit being effected when the rotary selector contact is on any position except a neutral position, which is adjustable, should any of said other switching devices be operated, this circuit energising relays RL1, RL2, contacts r2', r2" and r2"' closed upon operation of the relays completing, respectively, a hold circuit for K4, a circuit for energising an alarm A and an electromagnetic bonnet lock BL, and a circuit by-passing distributor contacts V whereby the vehicle is disabled Each of the switches K1-K3 ap- plies a voltage to the base of transistor T1, switch K1 applying this via a condensor C2 since a switch K'1 operated simultaneously therewith breaks the direct circuit. The resulting voltage at the emitter of transistor T1 energises transistors T3, T4 which switch in the relay RL1 for a time, determined by condensor C3, sufficient for hold contacts r2' to operate. Transistor T2 also applies a voltage to transistors T3 and T4 if a wire F is cut. An alternative normally energised electromagnetic bonnet lock BL' locks the bonnet if the main supply is cut. The switches K1, K'1, K2 and K4 are fitted on a pair of rods 27 secured either directly or, as shown, via a sleeve 34 to a cap 26 which has a plurality of circumferentially spaced projections 23 co-operating with corresponding recesses in the casing 21, the cap being liftable against the action of springs 29 to allow it to be rotated to determine a fresh neutral position for the rotary selector contact K4. The vehicle owner has then merely to adjust a disc K'4 secured to the sleeve 34 until a number corresponding to the setting is opposite a pointer 24, to enable him to start the vehicle by pressing a button 30 operating switch K1. |
